Perhaps you should try some spelling variations:
thanh trung » thanh tung
chieu sang » chieu sach, chieu xanh, nhieu tang
thong cong » tong cong, thong thong, phong chong
hieu lang » hieu quang, nhieu tang, hieu van
trung va » truong va, trang va, trung ha
dan toan » van toan, dan than, manh toan
toan cao » toan ban, toan tap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: doi ((chieu sang) OR (hieu lang)) - thanh trung va ((thong cong) or (trong cong)) dan toan cao~.
• If you are trying to use Boolean operators, they must be ALL CAPS: doi ((chieu sang) OR (hieu lang)) - thanh trung va ((thong cong) OR (trong cong)) dan toan cao*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "doi ((chieu sang) OR (hieu lang)) - thanh trung va ((thong cong) or (trong cong)) dan toan cao*".